Video compression is the process of compacting or condensing a digital video sequence into a smaller number of bits. Because uncompressed digital video typically requires a large bit-rate, video compression is often necessary for practical storage and transmission of digital video. Video compression is used in connection with a wide range of applications, such as digital television, Internet streaming video, DVD video, and so forth.
Video compression is achieved by removing redundancy. There are at least two types of redundancy that may be exploited to achieve video compression: temporal redundancy and spatial redundancy. Temporal redundancy refers to similarities between temporally adjacent frames, i.e., frames that succeed one another in time. Spatial redundancy refers to similarities within the same frame. Most video compression methods attempt to eliminate both temporal and spatial redundancy.
A video compression system typically includes an encoder and a decoder. The encoder converts the source video data (i.e., the video data to be stored, transmitted, etc.) into a compressed form. The decoder converts the compressed form back into a representation of the original video data. The encoder/decoder pair is often referred to as a codec.
H.264 (also known as MPEG-4 Part 10, or AVC, for Advanced Video Coding) is a video compression standard that was written by the ITU-T Video Coding Experts Group (VCEG) together with the ISO/IEC Moving Picture Experts Group (MPEG) as the product of a collective partnership effort known as the Joint Video Team (JVT). H.264 contains a number of features that allow it to compress video much more effectively than older standards.
One of the features that H.264 provides is known as data partitioning. Data partitioning is a useful error resilience tool when transmitting video under error-prone conditions. Data partitioning allows the use of unequal error protection so that more important data is given more protection than less important data.
The Real-Time Transport Protocol (RTP) is a protocol standard for the transport of real-time data, including audio and video, over either unicast or multicast networks. RTP is used in virtually all voice-over-IP architectures, for videoconferencing, media-on-demand, and other applications. A thin protocol, RTP supports content identification, timing reconstruction, and detection of lost packets.
At low bit-rates when using RTP for H.264 video transmission and when using H.264 data partitioning, high overhead due the headers can occur. The present disclosure relates to techniques for addressing this issue.